"""
Content hashing helpers.

A single canonical hash implementation is used everywhere page content is
fingerprinted (Document nodes at ingestion time, /ingest/check-updates
comparisons) so hashes computed at different times are comparable.
"""

import hashlib


def compute_content_hash(content: str) -> str:
    """
    Compute the canonical content hash for wiki page content.

    Args:
        content: Raw page content (markdown). None-safe: treated as "".

    Returns:
        Hex-encoded SHA-256 digest of the UTF-8 encoded content.

    Examples:
        >>> compute_content_hash("hello")
        '2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824'
    """
    return hashlib.sha256((content or "").encode("utf-8")).hexdigest()